Oil-well stimulator



Nov. 8, 1927. l

D. U. POWELL oIL WELL sTIMuLAToR Filed Feb. 25. 1926 Witwe/.xo

Patented Nov. 8, 1927.

UNITED STATES 1.648.242 PATENT OFFICE.

DALTON U. POWELL, F WOODSFIELD, OHIO, ASSIZGrIll'OIB'. OF ONE-HALF TO SAMUEL K. FRANK, OF WEEELING, WEST VIRGINIA.

OIL-WELL STINFULATOR.

Application mea February 25, 192e. serial No. 90,612.

The invention relates to theV stimulation of oil wells to increase production and has reference more particularly to apparatus adapted to supply hot fluid under pressure (preferablyair to a well which is not being worked. The ot liuid serves to melt any paraflin or analogous deposits in the` producing strata, loosens the sand in such strata, and gradually drives the freed oil lo away from the well in which the a paratus 1s used, toward other wells which e being worked Thus, the output of these wells may be materially increased.

Prior to m invention, I am aware that attempts have een made to reachthe producing strata with hot compressed air and with other heated fluids. However, such attempts have not obtained the results which have been sought, due primarily .to the fact that the fluid has so cooled by the time it reaches the producing strata, that it can have no appreciable effect upon the latter. It is the principal object of the present invention to provide a novel apparatus whereby the '25 desired results, heretofore unattainable, may

be readily attained.

With the foregoing and minor objects in view, the invention resides in the novel subject matter hereinafer described and claimed,

the description being supplemented by the accompanying drawing.

Figure 1 is an elevation partly in section showing the application of the invention to an oil well.

Fig. 2 is an enlarged sectional view partly in elevation.

Fig. 3 is a diagrammatic side elevation of down-flow and up-flow air heating coils which are associated withna heater within the well. A

l Fig. dista sectional view partlyy in elevation illustrating the electrical coupling which is employed between the .electric heater and a cable which supplies current-to i said heater, the plug and socket elements of said coupling bein shown in juxtaposition. The numeral 5 esignates an oil well, a

portion of which is provided with the usual easing -having a casing head 7 A. pipe line 8 passes throughv an opening in the head 7 and extends preferably to a point slightly above the producing strata'9, at which point, said pipe line is connected with a vertically elongated casing 10 having an anchor 11 at 'its lower end, about one-fourth of the length of said casing being preferably'submerged` 1n the oil standing in the well. Within the casing 10, I provide means for effectively heating Aair or other fluid which may be forced down the pipe line 8 under pressure. I prefer to make use of air, andat 11 on the drawing, I have indicated a pipe leading from an air compressor to an air heater, this heater .being connected by a pipe 12 with the. upper end of the pipe line 8. The heater may be oany desired construction, and for illustrative purposes, it includes a heating coil 13 and a burner 14 for heating the same. The air from the compressor is highly heated in the coil 13 and is forced down the pipe line 8 under pressure, but due to the length of said pipe line, the air necessarily cools to an appreciable extent. Therefore, I have made provision in the casing 10 for'again heating such so that it may finally be discharged into the well at a high temperature, insuring the best results.

Extending across the upper portion of the casing 10, is a'partition 15 and it will be seen that the fluid inlet 16 for said casing is above this partition.- The casing wall however is provided near Vits lower end, with a plurality of outwardly opening check valves 17 constituting fluid outlets. Below the partition 15, is an electric heater'18 of any desired construction, said heater' preferably comprising a cylindrical body having a projection 19 at its upper end and a. similar projection 20 at its lower end, the projection 19 bein tightly received in a central ope g in e partition 15, suitable packing being preferably employed to prevent leakage of air. The projection 20 is received in an opening at the center of an additional plate 21 which extends horizontally across the lower end portion of the casing 10, below the fluid outlets 17, and the heater is held in place by the two plates 15 and 21, which abut its ends as well as vengaging itsv projections 19 and 20. These two plates 15` and 21 are preferably clamped tightly against the `ends et the casing wall, fb upper and lower caps22'and 23 whic are threaded upon the ends of said wall, the ap 22 having the fluid inlet I6 to which the pipe line 8 is coupled, while the cap 23 is secured to the anchorll.

A down-flow, fluid heating coil 24 surrounds the heater 18 and is spaced from the wall of the casing Y10, and an 11p-flow fluid heating coil.28 also surrounds said heater and is spaced Vfrom the casing wall, the lower' v,ends of the two coils being connected'with each other as indicated at 26. The upper end of the down-,flow coil 24, passes through seen `that before the air from the pipe line 8 can discharge into the well, it must pass downwardly throu h the coil 24, around the full length f the eater 18, must then ass 'upwardly through the coil 25, throug out `the length of said heater, is then discharged into the casing 10, and must travel again to the lower portion of this casing before it can be discharged through the outlets 17. Thus treble heating of the air is effected so that when it is finally discharged, it is. at a high degree of temperature and will attain results which have never before been gotten.

Passing through an appropriate stuiing box 29 at the upper end of the pipe line 8, is a cable 30 having current supply Wires 31 for theheater 18, and novelvprovision is made, consisting of a unique electrical coupling, forthe purpose of operativelyl connecting the cable with the heater, when said cable is lowered through the pipe line 8, after installation of all other parts of the apparatus. In the present showing, a socket 32 is carried b the projection 19 at the upper end of the eater 18,A and a plu 33 is carriedby the lower end of the ca le 30, said cable being provided with a number of sink.

ers 34 which are instrumental in lowering it. The plug 33 is receivable in the socket 32, and said plug and socket are provided with .self-engaging contacts which establish an electrical connection between the wires 31 and the heating element of the heater 18,

the two 'terminals of this heating element being indicated at 35 in Fig. 4. In the present showing, the terminals 35 are connected with suitably mounted and insulated contacts 36 which are positioned at-the tapered bottom 37 of the socket 32. These contacts 36 are cooperable with other contacts 38 carried by the plug 33, the last named contacts being of course insulated from each other in any desired manner., Appropriately connected to the contact 38, are the wires 31, so that when saidcontacts 38 are tightly seated upon the contacts 36, the circuit for the heater 18 may be completed. The contacts 38 are preferably of substantially semi-circular form to insure engagement with the contacts 36, and they may well be located on a pointed-lower end of the lug 33, this formation serving to ei'ectivell;y ide `the lug into the socket, as the ca le 30 is owered.

To insure tight seating of the contacts 38- plug and the socket are provided with alternate ribs 39 and grooves 40, the ribs of the plug being downwardly tapered to sharp points, while those of the socket are upwardly tapered, so that they cannot, catch.

upon each other. All of the ribs and grooves are coarsely pitched in a helical manner and they cause tight seating of the plug-carried contacts 38 against the stationary contacts 36, when the plug finally descends into the,

socket.

Preferably used in connection with, the features above described, is a pipe41 passing through the casing head r7 and extendin downwardly into the well' to v,any desire` extent. A pressure gage`(not shown) may be applied to the outer end ofi this Apipe to gage the pressure within the well, ,or by leaving said pipe open, fluid from the well mayl discharge through it under-the influence of the air pressure, should this be desired. Also, should it occur that the producing strata 9 around the well is becoming too d for the production of its best resultso1l may be forced into the well through this pipe. A suitable packer 42 preferably extends across the caslng 6 and packs the space between this casing and the pipe line 8, the above mentioned pipe 41 eing passed through an opening in said packer.

It will be seen from the foregoing that a very efficient apparatus has been rovided for attaining the desired end, and t at such apparatus embodies a number of unique as sembla es and details of construction. These are prelerably followed, but it is to be understood tllat within the scope of the invention as claimed, numerous variations may be made. Y

I claim:

1. In a roduction stimulator for oil wells, an e ongated heater having projections at its ends, a cylinder around said heater, a pair of plates contacting with the ends of the heater and having openings receiving said projections, caps threaded on the ends of said cylinders, surroundin said plates and clamping the latter tightly against the cylinder ends and the heater ends, one of said caps having a fluid inlet, means placing the interior o in communication with the cylinder, and a Huid outlet`from said cylinder.

2. In a production stimulator for oil wells; a pipe to extend into the well, an electric heater mounted at the lower end of said pipe, a cable having current supply Wiresy for the heater, said cable be1n weighted at its lower end to be lowere said one cap through said pi e, and self-engaging con- Lesespa cally connecting the -two when said cable is lowered.

3. In ay production stimulator for oil wells, a pipe to extend into the well, an electric heatermounted at the lower end of said pipe, a cable having current supply Wires Jfor the heater, said cable being weighted at its lower end to be lowered through said pipe, and a self-engaging electrical coupling for connecting the cable and heater, pling comprising an intertting plug and socket havin coacting contacts, said plug and socket icing providedl with 1steeply itched helical ribs and grooves adapted to mter-engage and hold the contacts in tight engagement with each other.

4. In a vproduction stimulator for oil wells, a casingfor disposition in the well, said casing having a fluid outlet, a fluid heating conductor in said casing having an outlet into the latter, means for conducting fluid to said conductor from the top of the well, and means located and heated in the casing for continuously and uninterruptedly heating said conductor; said conductor comprising a down-How and an up-low coil communicating with each other at their lower ends, the fluid being conducted to said said couv down-flow coil, the outlet end of said uplow coil heing remote from the outlet of .the casing for' the purpose'set forth.

5. In a production stimulator .for oil wells, a verticall elongated casing for disposition in a wel tition between its ends, a fluid inlet above the partition and a. fluid outlet below said partition, a fluid heating conductor in the casing below the partition and discharging into this portion of said casing, said con'- ductor having a fluid inlet above said partition,A and means in said casing below the partition for continuously and uninterruptedly'heating the fluid as it passes through said conductor,.said means being heated 1n the casing; said conductor comprising a down-flow coil and an up-flow coil communieating with each other -at- Said down-flow coil having its inlet end passed through said partition, of the up-flow coil being remote from the fluid outlet of said casing for the purpose set forth. 1

In testimony whereof I have hereunto affixed my signature.

DALTON U. POWELL.

said casing having a pan;n

their lower ends,

the outlet end l 

